JPH03187146A - Field emission electron microscope - Google Patents
Field emission electron microscopeInfo
- Publication number
- JPH03187146A JPH03187146A JP1326134A JP32613489A JPH03187146A JP H03187146 A JPH03187146 A JP H03187146A JP 1326134 A JP1326134 A JP 1326134A JP 32613489 A JP32613489 A JP 32613489A JP H03187146 A JPH03187146 A JP H03187146A
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- electrostatic lens
- electron
- cathode
- accelerating
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000010894 electron beam technology Methods 0.000 claims abstract description 13
- 238000000605 extraction Methods 0.000 claims description 16
- 238000003384 imaging method Methods 0.000 claims description 3
- 230000001133 acceleration Effects 0.000 description 12
- 238000010586 diagram Methods 0.000 description 3
- 239000007787 solid Substances 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000001678 irradiating effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/02—Details
- H01J37/24—Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for
- H01J37/243—Beam current control or regulation circuits
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/02—Details
- H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement or ion-optical arrangement
- H01J37/06—Electron sources; Electron guns
- H01J37/073—Electron guns using field emission, photo emission, or secondary emission electron sources
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Electron Sources, Ion Sources (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は電界放出型電子顕微鏡に係り、特に、電子引出
電圧や陰極への電子加速電圧が変化しても常に一定の明
るさで電子ビームを試料上に照射させることを図った電
界放出型電子顕微鏡に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a field emission electron microscope, and in particular, the present invention relates to a field emission electron microscope, and in particular, the present invention relates to a field emission electron microscope. This invention relates to a field emission electron microscope designed to irradiate a sample with light.
第４図に電界放出陰極を用いた電子顕微鏡の光学系の従
来例を示す。静電レンズ２内の第１陽極（電子引出電極
）３に印加された電子引出電圧ｖ１により電界放出陰極
１からの放出電流が制御される。第２陽極（初段加速電
極）４には、静電レンズ２のレンズ作用を制御する制御
電圧Ｖ２が印加される、第２陰極４以降には股間に等電
圧がかかるように、高抵抗９が等分割されて各分割電圧
が印加される。１！子引出電圧ｖ１の変化に連動して。FIG. 4 shows a conventional example of an optical system for an electron microscope using a field emission cathode. The emission current from the field emission cathode 1 is controlled by the electron extraction voltage v1 applied to the first anode (electron extraction electrode) 3 in the electrostatic lens 2. A control voltage V2 that controls the lens action of the electrostatic lens 2 is applied to the second anode (first-stage accelerating electrode) 4. A high resistance 9 is applied to the second and subsequent cathodes 4 so that an equal voltage is applied to the crotch. It is equally divided and each divided voltage is applied. 1! In conjunction with changes in the sub-output voltage v1.
静電レンズ２の結像位置を制御する手段は特開昭６０−
１１７５３４号に示されるごとく、公知である。The means for controlling the image forming position of the electrostatic lens 2 is disclosed in Japanese Patent Application Laid-Open No. 1986-
As shown in No. 117534, it is publicly known.
ここで１例えば電子ビームを試料に照射して得られる特
性Ｘ線を検出して試料の元素組成を定量分析する際には
、試料に照射されるビーム電流を一定にする必要がある
が、そのために制御電圧ｖ２をどのように制御すれば良
いかについては、今まで明らかにされていなかった。い
ま、静電レンズ２の像を試料７の面上あるいは面より所
定深さの点に集束させるコンデンサレンズ５の主面と静
電レンズ２との間に電子ビームの電流を制限する絞り６
が配置されており、この絞りと９電レンズ２の結像位置
との距離をＬとおく０次に、直径２γの絞り６で制限さ
れる静電レンズ出射角をβとおくと、２γ＝２Ｌβの関
係となる。また、静電レンズ出射角βに対応する陰極出
射角をαとおくと、直径２Ｌβの絞り６で制限される陰
極出射角はαとなる。したがって、放出陰極１の放出角
電流密度（単位立体角当たりの放出電流）をωとおくと
、絞り６上のビーム電流はπα２ωとなる。Here, 1. For example, when quantitatively analyzing the elemental composition of a sample by detecting the characteristic X-rays obtained by irradiating the sample with an electron beam, it is necessary to keep the beam current irradiated to the sample constant. Until now, it has not been clarified how to control the control voltage v2. Now, between the main surface of the condenser lens 5 that focuses the image of the electrostatic lens 2 on the surface of the sample 7 or a point at a predetermined depth from the surface, and the electrostatic lens 2, there is an aperture 6 that limits the current of the electron beam.
is arranged, and let the distance between this aperture and the imaging position of the 9-electro lens 2 be L. Then, let β be the exit angle of the electrostatic lens limited by the diaphragm 6 with a diameter of 2γ, then 2γ= The relationship is 2Lβ. Further, if the cathode emission angle corresponding to the electrostatic lens emission angle β is set as α, the cathode emission angle limited by the aperture 6 having a diameter of 2Lβ becomes α. Therefore, when the emission angular current density (emission current per unit solid angle) of the emission cathode 1 is set as ω, the beam current on the aperture 6 becomes πα2ω.
放出角電流密度ωは電子引出電圧Ｖ、に連動して変化す
る。所望のωを得るための■１は放出陰極ごとに異なる
。また、放出陰極を加熱し表面を清浄化処理すると陰極
の曲率半径が変化するので、ωとＶ、との関係は経時的
にも変化する。このように、所望のωを維持するために
は、電子引出電圧ｖ１を変化させていくことが必要であ
る。しかし、ｖｌの変化に応じて静電レンズ作用も変化
してしまうので、絞り６で制限されるビーム電流を一定
にするためには、制御電圧■２で静電レンズ作用を調整
する必要がある。The emission angular current density ω changes in conjunction with the electron extraction voltage V. (1) to obtain the desired ω differs depending on the emission cathode. Further, when the emission cathode is heated and its surface is cleaned, the radius of curvature of the cathode changes, so the relationship between ω and V also changes over time. In this way, in order to maintain the desired ω, it is necessary to change the electron extraction voltage v1. However, the electrostatic lens action changes as vl changes, so in order to keep the beam current limited by the aperture 6 constant, it is necessary to adjust the electrostatic lens action with the control voltage ■2. .
これに対して、前記特開昭６０−１１７５３４号にも、
制御電圧Ｖ２を、電子引出電圧Ｖ０の変化に連動して制
御するとの記載があるが、しかし、その場合の制御は、
静電レンズの結像位置を制御するもので、絞りでのビー
ム電流を一定にする制御を行うものではない。On the other hand, also in the above-mentioned Japanese Patent Application Laid-Open No. 117534/1983,
There is a description that the control voltage V2 is controlled in conjunction with changes in the electron extraction voltage V0, but in that case, the control is as follows.
It controls the imaging position of the electrostatic lens, and does not control the beam current at the aperture to be constant.
本発明の目的は、電子引出電圧ｖ１あるいは陰極に印加
する電子加速電圧Ｖ０をどのように調整した場合も、絞
りで制限されるビーム電流が常に一定となり、一定の明
るさで電子ビームを試料上に照射することのできる電界
放出型電子顕微鏡を提供することにある。The purpose of the present invention is to keep the beam current limited by the aperture constant no matter how the electron extraction voltage v1 or the electron acceleration voltage V0 applied to the cathode is adjusted, so that the electron beam can be directed onto the sample at a constant brightness. It is an object of the present invention to provide a field emission electron microscope that can irradiate light.
上記目的を達成するために１本発明においては。 In order to achieve the above object, one aspect of the present invention is as follows.
第２陽Ｆｉ（初段加速電極）４以降の加速電極に印加す
る制御電圧Ｖ２を、Ｌβ／αが一定となるように、第１
陽極（電子引出電極）３に印加する電子引出電圧■、あ
るいは陰極１に印加する加速電圧Ｖ０の変化に連動して
変化させる印加電圧制御手段を設ける。The control voltage V2 applied to the accelerating electrodes after the second positive Fi (first-stage accelerating electrode) 4 is adjusted so that Lβ/α is constant.
An applied voltage control means is provided which changes the electron extraction voltage (2) applied to the anode (electron extraction electrode) 3 in conjunction with changes in the acceleration voltage V0 applied to the cathode 1.
直径が２γ＝２Ｌβの絞り６でのビーム電流は。 The beam current at the aperture 6 whose diameter is 2γ=2Lβ is.
前述したようにπα２ωとなる。Ｌβ／αが一定であれ
ば直径２Ｌβの絞り６で制限される陰極出射角αが一定
となる。したがって、ωが一定値を維持し、かつ、Ｌβ
／α＝Ｋ（一定値）の条件を満足するように、Ｖ２．Ｖ
ｌ、Ｖ。の関係を制御すれば、絞り６でのビーム電流は
常に一定となり、電子ビームを常に一定の明るさで試料
に照射できることになる。As mentioned above, πα2ω. If Lβ/α is constant, the cathode emission angle α, which is limited by the aperture 6 having a diameter of 2Lβ, will be constant. Therefore, ω maintains a constant value and Lβ
V2. so that the condition of /α=K (constant value) is satisfied. V
l, V. By controlling this relationship, the beam current at the aperture 6 will always be constant, and the sample can be irradiated with the electron beam at a constant brightness.
ｖ２の具体的な制御作用を第２図を用いて説明する。第
２図の実線臼１（イ）はＶ、＝ ２００ｋＶとし、また
実線曲線（ロ）はＶ、＝ １００ｋＶとし、いずれも、
電界放出電流が一定値（後述の実施例では３０μＡ）を
維持しながら、βＬ／α＝に□（ある一定値）となるＶ
、、Ｖユの関係曲線である。The specific control action of v2 will be explained using FIG. In Fig. 2, solid line mill 1 (a) is set to V, = 200 kV, and solid line curve (b) is set to V, = 100 kV, both of which are
V such that βL/α=□ (certain constant value) while maintaining the field emission current at a constant value (30 μA in the example described later)
, , V Yu relationship curve.
これらの関係曲線は、静電レンズの電子軌道の計算から
、あるいは後述するように、実験的に求められる。すな
わち、 Ｖ、、 Ｖｌ、 Ｖ、の関係が実線曲線（イ）
あるいは（ロ）の上にあれば、電界放出電流は一定値、
かつ、Ｌβ／α＝に、（＝一定値）の条件を満足する。These relationship curves can be obtained from calculations of electron trajectories of the electrostatic lens or experimentally as described below. In other words, the relationship between V,, Vl, and V is a solid curve (A)
Or, if it is above (b), the field emission current is a constant value,
In addition, the condition that Lβ/α=(=constant value) is satisfied.
これは、（Ｖ、＝Ａ。This is (V,=A.
Ｖ、＝４ｋＶ、Ｖ、＝２００ｋＶ）（７）組合せのとき
、（Ｖ、＝Ｂ、Ｖ、＝６ｋＶ、Ｖ。：２００ｋＶ）の組
合せのとき、あるいは、（Ｖ、：Ｃ，Ｖ１＝４ｋＶ。V, = 4kV, V, = 200kV) (7) When the combination (V, = B, V, = 6kV, V.: 200kV), or (V,: C, V1 = 4kV).
Ｖ、＝ｌ ０ＯｋＶ）の組合せのとき、のいずれの場合
も電界放出電流がある一定値に保たれ、かつ。V, = l 0OkV), the field emission current is kept at a certain constant value in both cases, and.
Ｌβ／αもある一定値であり、したがって、前述した理
由により、絞りでのビーム電流は常に一定になることを
意味する。したがって、この実線曲線（イ）及び（ロ）
で示されるＶ、、 Ｖｌ、 Ｖ、の関係を、制御指令を
発生する制御演算部に記憶させておき、Ｖｌ、Ｖ、の変
化に連動してＶ２が実線曲線（イ）、（ロ）上に乗るよ
うに制御することにより、絞りでのビーム電流を一定に
、これにより試料に照射される電子ビームの明るさを一
定に制御できることになる。Lβ/α is also a certain constant value, which means that the beam current at the aperture is always constant for the reason mentioned above. Therefore, this solid curve (a) and (b)
The relationship between V,, Vl, and V, shown as By controlling the electron beam so as to maintain the beam current, the beam current at the aperture can be kept constant, and thereby the brightness of the electron beam irradiated onto the sample can be controlled to be constant.
以下１本発明の一実施例を第１図により説明する。静電
レンズ２の像を試料７上あるいは所定深さ位置に結像さ
せるコンデンサレンズ５の主面と静電レンズ２の間の光
軸上にはビーム電流を制限する絞り６が配置されている
。演算部２４には、電子引出電圧Ｖ１、陰極加速電圧Ｖ
、に対して、Ｌβ／αの値が一定となる条件を満足する
制御電圧ｖ２の値がデータとして記憶されているか、あ
るいは関数式ｖｔ＝ｆ（ｖ。、ｖｌ）として与えられて
いる。このｖ２とＶｏ＝ Ｖｘとの関係は、静電レンズ
中の電子の軌道を計算することによって求められるが、
試料上のビーム電流を計測して、ｙｅｔ■□の組合せに
対して、試料上のビーム電流が一定となるようなり２の
値を実験的に求めることもできる０例えば、Ｖ、＝１０
０ｋＶ、２００ｋＶ。An embodiment of the present invention will be described below with reference to FIG. An aperture 6 that limits the beam current is arranged on the optical axis between the main surface of the condenser lens 5 that forms the image of the electrostatic lens 2 on the sample 7 or at a predetermined depth position and the electrostatic lens 2. . The calculation unit 24 has an electron extraction voltage V1, a cathode acceleration voltage V
, the value of the control voltage v2 that satisfies the condition that the value of Lβ/α is constant is stored as data or given as a function equation vt=f(v., vl). The relationship between v2 and Vo=Vx can be found by calculating the orbit of the electron in the electrostatic lens, but
By measuring the beam current on the sample, the value of 2 can be determined experimentally so that the beam current on the sample becomes constant for the combination of yet
0kV, 200kV.
Ｖ１＝４〜７ｋＶ１．：対して、Ｌβ／ａ＝に１を満た
すｖ２の値が、第２図に示す曲線（イ）、（ロ）として
演算部２４に記憶されているか、ある関数形で与えられ
ている。V1=4~7kV1. : On the other hand, the value of v2 that satisfies Lβ/a=1 is stored in the arithmetic unit 24 as curves (a) and (b) shown in FIG. 2, or is given in a certain functional form.
まず、例えば、Ｖｏ＝２００ｋｖにするために。First, for example, to make Vo=200kv.
加速電圧制御電源２１を通じ、加速電圧供給電源１８よ
り、陰極加速電圧ｖ０が供給される０次に。The zeroth order is supplied with the cathode acceleration voltage v0 from the acceleration voltage supply power supply 18 through the acceleration voltage control power supply 21.
第１陽極電圧制御電源２２を通じ、第１陽極電圧供給電
源１９より、電子引出電圧ｖ１が、第１陽極３に流れる
電界放出電流が例えば３０μＡになるまで印加される。An electron extraction voltage v1 is applied from the first anode voltage supply power source 19 through the first anode voltage control power source 22 until the field emission current flowing through the first anode 3 reaches, for example, 30 μA.
ここでＶ１＝４ｋＶで電界放出電流が所望値３０μＡと
なったとして、この値の所テ固定スル、演算部２４は、
ｖ、＝２００ｋＶ。Here, assuming that V1 = 4 kV and the field emission current is a desired value of 30 μA, this value is fixed at a specified value and the calculation unit 24 calculates the following:
v, = 200kV.
■□＝４ｋＶの値をそれぞれの電ｇ２１．２２より読み
取り、Ｌβ／α＝に、を満足するＶ、＝Ａを演算し、第
２陽極電圧制御電源２３を通じ、第２陽極電圧供給電源
２０より、制御電圧ｖ２としてＶ、＝Ａを供給するよう
に指令信号を発生する。Read the value of □ = 4kV from each voltage g21.22, calculate V, =A that satisfies Lβ/α=, , a command signal is generated to supply V,=A as the control voltage v2.
もし、同じ３０μＡの電界放出電流を流すのにＶ１＝６
ｋＶであった場合には、演算部２４でＬβ／α＝に、を
満足するｖ２＝Ｂを求めて、制御電圧ｖ２をＶ、＝Ｂと
するように指令する０以上の制御操作により、絞り６で
制限されるビーム電流は、Ｖ、＝４ｋＶ＋７）ときもＶ
□＝６ｋｖのときも、自動的に等しいビーム電流となる
６以上の制御方式は、本発明の請求項１に対応し、制御
電圧Ｖ□を、電子引出電圧Ｖ１に連動して変化させる制
御である。If the same field emission current of 30μA flows, V1=6
kV, the calculation unit 24 calculates v2=B that satisfies Lβ/α=, and performs a control operation of 0 or more to instruct the control voltage v2 to be V,=B. The beam current limited by 6 is V, = 4kV + 7) also when V
The control method of 6 or more that automatically makes the beam current equal even when □=6kV corresponds to claim 1 of the present invention, and is a control method in which the control voltage V□ is changed in conjunction with the electron extraction voltage V1. be.
陰極加速電圧Ｖ、に連動させて、照射系の動作条件を一
定に保つように制御電圧ｖ２を特徴する請求項２に対応
する方式とすることもできる０例えば、電子引出電圧は
Ｖ１＝４ｋＶに固定し、陰極加速電圧ｖ０がＶ、＝１０
０ｋＶと変わった場合には、演算部２４よりｖ２＝Ｃの
制御電圧となるように指令することにより、Ｌβ／α＝
にユの条件が満足され、絞りでのビーム電流は一定とな
る。A system corresponding to claim 2 may also be used, in which the control voltage v2 is linked to the cathode acceleration voltage V, so as to keep the operating conditions of the irradiation system constant. For example, the electron extraction voltage may be set to V1 = 4 kV. Fixed, cathode acceleration voltage v0 is V, = 10
If it changes to 0kV, the calculation unit 24 instructs the control voltage to be v2=C, so that Lβ/α=
The y condition is satisfied, and the beam current at the aperture becomes constant.
なお、第２図では破線曲線で示すように。In addition, as shown by the broken line curve in FIG.
Ｌβ／α＝に、の値に対するｖ２が描かれているが、こ
のように、Ｌβ／αの複数個の値に対してｖ２をそれぞ
れ設定することもでき、これにより、電界放出電流を変
えずに、絞りで制限されるビーム電流を制御することも
可能である。Although v2 for the value of Lβ/α is drawn in Lβ/α, it is also possible to set v2 for each of multiple values of Lβ/α in this way, thereby keeping the field emission current unchanged. Additionally, it is also possible to control the beam current, which is limited by the aperture.
今までの図は、静電レンズが実像側に結像する場合につ
いて説明してきたが、静電レンズが虚像側に結像する場
合にも、第３図に示すように、静電レンズ後段のコンデ
ンサレンズ主面と静電レンズの間に電子ビーム電流を制
限する絞りを置き。The figures so far have explained the case where the electrostatic lens forms an image on the real image side, but even when the electrostatic lens forms an image on the virtual image side, as shown in Figure 3, the electrostatic lens rear stage An aperture is placed between the main surface of the condenser lens and the electrostatic lens to limit the electron beam current.
その絞りと静電レンズの虚像側の結像位置との間の距離
りに静電レンズの角度倍率β／αを掛けたＬβ／αが一
定となるように、制御電圧ｖ３を、電子引出電圧ｖ１あ
るいは陰極加速電圧ｖ０に連動させて制御することによ
り、絞りで制限されるビーム電流を一定に保つことがで
きる。The control voltage v3 is adjusted so that the electron extraction voltage By controlling in conjunction with v1 or cathode acceleration voltage v0, the beam current limited by the aperture can be kept constant.
以上説明したように１本発明によれば、静電レンズ後段
のコンデンサレンズ主面と静電レンズとの間に電子ビー
ム電流を制限する絞りを置き、この絞りと静電レンズの
結像位置との間の距離りに静電レンズの角度倍率β／α
を掛けたＬβ／αが一定となるように、制御電圧ｖ２を
、電子引出電圧ｖ１あるいは陰極加速電圧ｖ０の変化に
連動して制御することにより、絞りで制限されるビーム
電流が常に一定となり、ｖｌやｖｏのどのような変化に
対しても常に一定の明るさで電子ビームを試料上に照射
することができる。As explained above, according to one aspect of the present invention, an aperture for limiting the electron beam current is placed between the main surface of the condenser lens at the latter stage of the electrostatic lens and the electrostatic lens, and the image forming position of the aperture and the electrostatic lens is The angular magnification β/α of the electrostatic lens is the distance between
By controlling the control voltage v2 in conjunction with changes in the electron extraction voltage v1 or the cathode acceleration voltage v0 so that Lβ/α multiplied by Lβ/α remains constant, the beam current limited by the aperture becomes constant. The electron beam can be irradiated onto the sample with constant brightness regardless of any changes in vl or vo.
第１図、第３図はそれぞれ本発明の一実施例の構成図、
第２図は本発明の詳細な説明図で演算部に記憶あるいは
演算されるＶ、、Ｖ、、Ｖ、の関係曲線を示す、第４図
は従来例の構成図である。
符号の説明
１・・・電界放出陰極 ２・・・静電レンズ３・・
・第１陽極 ４・・・第２陽極５・・・コンデ
ンサレンズ ６・・・絞り７・・・試料
９・・・高抵抗１８・・・加速電圧供給電源
１９・・・第１陽極電圧供給電源
２０・・・第２陽極電圧供給電源
２１・・・加速電圧制御電源
２２・・・第１ｕＩ極電圧制御電源
２３・・・第２陽極電圧制御電源
２４・・・演算部FIG. 1 and FIG. 3 are block diagrams of an embodiment of the present invention, respectively.
FIG. 2 is a detailed explanatory diagram of the present invention, showing a relational curve of V, , V, , V stored or computed in the computing section. FIG. 4 is a configuration diagram of a conventional example. Explanation of symbols 1... Field emission cathode 2... Electrostatic lens 3...
・First anode 4...Second anode 5...Condenser lens 6...Aperture 7...Sample
9...High resistance 18...Acceleration voltage supply power supply 19...First anode voltage supply power supply 20...Second anode voltage supply power supply 21...Acceleration voltage control power supply 22...1uI pole voltage Control power supply 23...Second anode voltage control power supply 24...Arithmetic unit
Claims (1)
る電子引出電極及び引き出された電子線を加速する２段
以上の加速電極を有する静電レンズと、この静電レンズ
による像を試料上あるいは近傍の所定位置に集束させる
集束レンズと、上記静電レンズと上記集束レンズとの間
に配置されてビーム電流を制限する絞りとを備えた電界
放出型電子顕微鏡において、初段加速電極を含む少なく
とも１つ以上の加速電極に印加する電圧を、陰極出射角
をα、静電レンズ出射角をβ、静電レンズの結像位置と
絞り面との距離をＬとしてＬβ／αが一定となるように
、電子引出電圧の変化に連動して制御する印加電圧制御
手段を備えたことを特徴とする電界放出型電子顕微鏡。 ２、請求項１記載の初段加速電極を含む少なくとも１つ
以上の加速電極に印加する電圧を、前記Ｌβ／αが一定
となるように、陰極に印加する電子加速電圧の変化に連
動して制御する印加電圧制御手段を備えたことを特徴と
する電界放出型電子顕微鏡。[Claims] 1. An electrostatic lens having a field emission cathode, an electron extraction electrode for field-emitting electrons from the cathode, and two or more stages of accelerating electrodes for accelerating the extracted electron beam, and this electrostatic lens. In a field emission electron microscope, the first stage is equipped with a focusing lens that focuses the image of The voltage applied to at least one accelerating electrode including the accelerating electrode is expressed as Lβ/α where α is the cathode emission angle, β is the electrostatic lens emission angle, and L is the distance between the imaging position of the electrostatic lens and the aperture plane. 1. A field emission electron microscope characterized by comprising applied voltage control means that controls applied voltage in conjunction with changes in electron extraction voltage so that the voltage is constant. 2. Controlling the voltage applied to at least one accelerating electrode including the first-stage accelerating electrode according to claim 1 in conjunction with changes in the electron accelerating voltage applied to the cathode so that the Lβ/α is constant. A field emission electron microscope characterized in that it is equipped with applied voltage control means.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1326134A JP3056757B2 (en) | 1989-12-18 | 1989-12-18 | Field emission electron microscope |
| US07/627,976 US5134289A (en) | 1989-12-18 | 1990-12-17 | Field emission electron device which produces a constant beam current |
| EP90313855A EP0434370B1 (en) | 1989-12-18 | 1990-12-18 | Field emission electron device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1326134A JP3056757B2 (en) | 1989-12-18 | 1989-12-18 | Field emission electron microscope |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03187146A true JPH03187146A (en) | 1991-08-15 |
| JP3056757B2 JP3056757B2 (en) | 2000-06-26 |
Family
ID=18184441
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1326134A Expired - Fee Related JP3056757B2 (en) | 1989-12-18 | 1989-12-18 | Field emission electron microscope |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US5134289A (en) |
| EP (1) | EP0434370B1 (en) |
| JP (1) | JP3056757B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999050651A1 (en) * | 1998-03-27 | 1999-10-07 | Hitachi, Ltd. | Pattern inspection device |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11250850A (en) | 1998-03-02 | 1999-09-17 | Hitachi Ltd | Scanning electron microscope, microscope method, and interactive input device |
| EP1249855B1 (en) * | 2001-04-09 | 2008-07-09 | ICT Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik mbH | Device and method for controlling focussed electron beams |
| JP3914750B2 (en) | 2001-11-20 | 2007-05-16 | 日本電子株式会社 | Charged particle beam device with aberration correction device |
| EP1426997A1 (en) | 2002-12-06 | 2004-06-09 | ICT, Integrated Circuit Testing Gesellschaft für Halbleiterprüftechnik Mbh | Field emitter beam source and method for controlling a beam current |
| JP4610182B2 (en) * | 2003-12-05 | 2011-01-12 | 株式会社日立ハイテクノロジーズ | Scanning electron microscope |
| JP4611755B2 (en) * | 2005-01-13 | 2011-01-12 | 株式会社日立ハイテクノロジーズ | Scanning electron microscope and imaging method thereof |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3936756A (en) * | 1971-04-30 | 1976-02-03 | Nihon Denshi Kabushiki Kaisha | Field emission electron gun having automatic current control |
| US3786305A (en) * | 1972-05-15 | 1974-01-15 | Hitachi Ltd | Field emission electron gun |
| JPS59134539A (en) * | 1983-01-21 | 1984-08-02 | Hitachi Ltd | Device provided with field emission type electron gun |
| JPH0766772B2 (en) * | 1983-11-30 | 1995-07-19 | 株式会社日立製作所 | Multi-stage acceleration field emission electron microscope |
-
1989
- 1989-12-18 JP JP1326134A patent/JP3056757B2/en not_active Expired - Fee Related
-
1990
- 1990-12-17 US US07/627,976 patent/US5134289A/en not_active Expired - Lifetime
- 1990-12-18 EP EP90313855A patent/EP0434370B1/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO1999050651A1 (en) * | 1998-03-27 | 1999-10-07 | Hitachi, Ltd. | Pattern inspection device |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0434370B1 (en) | 1996-06-12 |
| EP0434370A2 (en) | 1991-06-26 |
| US5134289A (en) | 1992-07-28 |
| EP0434370A3 (en) | 1991-07-31 |
| JP3056757B2 (en) | 2000-06-26 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH03187146A (en) | Field emission electron microscope | |
| JP3697810B2 (en) | Transfer device using electron beam | |
| US4694346A (en) | Method and apparatus for gating image tubes | |
| US20030006377A1 (en) | Tandem acceleration electrostatic lens | |
| JPH09260237A (en) | Electron gun, electron beam equipment and electron beam irradiation method | |
| Kuroda et al. | Analysis of accelerating lens system in field‐emission scanning electron microscope | |
| JP2765829B2 (en) | Focused ion beam processing equipment | |
| JP3469404B2 (en) | Field emission type charged particle gun and charged particle beam irradiation device | |
| JP2002324507A (en) | X-ray generator and x-ray device using it | |
| JP3031043B2 (en) | Ion irradiation apparatus and control method thereof | |
| JPH09129166A (en) | Electron gun | |
| JPH0370340B2 (en) | ||
| JPH07142023A (en) | Parallel scan type ion implantation device | |
| JP2503359B2 (en) | Charged particle beam drawing device | |
| JP3234373B2 (en) | Magnetic field type electron lens and electron beam device using the same | |
| JPH0343647Y2 (en) | ||
| JPS62184754A (en) | Focused ion beam device | |
| JP3123861B2 (en) | Electron beam equipment | |
| JPH063720B2 (en) | Focused ion beam device | |
| JPH0559577B2 (en) | ||
| JPH0518838Y2 (en) | ||
| JPH0727859B2 (en) | Charged particle beam writing system | |
| JPH1196950A (en) | Method and device for radiating highly stable charged particle beam | |
| JPS63216342A (en) | Charged-particle beam lithography device | |
| JPS6289827A (en) | Method for controlling electron beam in electron beam heating |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080414 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090414 Year of fee payment: 9 |
|
| LAPS | Cancellation because of no payment of annual fees |